After signed in to the Azure Management portal, navigate to the Service Bus section in the left pane.

Next select the “Create”-button in the lower center bar of the portal (not the “New”-button) to create a new Service Bus namespace, only. We only need to create a namespace since all the topics and subscriptions
are created by GeRes2, automatically.

After created successfully, select the new namespace in the list of namespaces as shown below and click on the “Connection Information” button in the center, lower toolbar of the portal. Copy the Service Bus connection string from the dialog
popping up since it is the one you need for GeRes2.

Next you need to adjust the service configuration of the GeRes2 backend. For this purpose, in the GeRes2-solution open the appropriate service configuration file (*.cscfg, by default the solution includes a *.cscfg for local debugging called ServiceConfiguration.Local.cscfg
which you can use to use this service bus namespace for local debugging).

Update the service bus configuration settings of all roles in the *.cscfg file. For each role you’ll find a setting called “Geres.Messaging.ServiceBusConnectionString” into which you need to paste the connection string you copied earlier
in step 4. A sample-excerpt is shown below:
You’ll need to change the Service Bus connection string three times, one time for each role-configuration as highlighted in the screen shot above.

That’s it, after you’ve configured Service Bus you need to configure Azure Active Directory and Storage if you haven’t done this before. For further details on these two other topics please look at: